Two weeks ago, Donald Collins walked into the Forest Deli in Arlington with an unusual request. He asked the owner of the deli, Pauline Cohen, if she would mind making him an apple pie. He told her he could supply the apples.

"I said, 'Of course, I'd be glad to,' " Pauline Cohen said. "But I told him to make sure they weren't eating apples because they don't make a good pie."

Collins is one of many loyal customers who return to the Forest Deli day after day and week after week, for coffee, sandwiches, good conversation and sometimes a favor. Like most of them, he is sad that the deli will close next month.

"I sure wish a petition could keep these people here," he said.

Pauline and Jack Cohen, 68 and 74, respectively, opened their business in the Arlington Forest Shopping Center 43 years ago. Now they have decided to retire. "I wouldn't say I'm happy about closing," Jack Cohen said. "It's going to take a while to get over it. We're going to miss our customers."

But he admits that a scheduled rent hike for their space would require that he and his wife work seven days a week to keep the place running. As it is, the deli is almost a full-time operation for both of them.

The Cohens have run the place alone since June 1983. Five days a week they get up at 5 in the morning to open their doors for their first customer at 5:40 a.m.

Looking back over the years, Pauline Cohen says the business was hardest in the beginning. Shortly after the couple was married and moved to Arlington in 1940, they decided to open a grocery store. They fell in love with a spot in the then brand-new Arlington Forest Shopping Center off Arlington Boulevard but were told they were not welcome because they were Jewish.

"It was posted on the boulevard. It said in big print, "This is a restricted area,' " Pauline Cohen said. But six months later, the owner approached the Cohens and offered to lease them space in the shopping center.

"We were here six months alone and it was a struggle," Pauline Cohen recalled recently. "The first 18 months, we worked every day."

"People weren't too happy about having us because we were Jewish," she added. "But it wore off because we asserted ourselves. They learned to like us because we were nice people. I've learned that a smile goes a long way and I've learned you treat everyone the same. You're courteous and polite. People respect you for that. They come back."

Mickel Brincat, a computer systems operator in the U.S. Coast Guard's office of personnel, is one of those people. Almost every afternoon about 3 he drops in for a club sandwich and some good company.

What keeps him coming back? "Their decency toward people," Brincat said. "They treat people with respect regardless of who they are. They allow credit. That's a value that's gone out the window with today's fact-paced world."

In addition to long hours and an open-minded attitude, Pauline Cohen said adjustment and flexibility have been crucial to survival of the business. The couple ran a grocery store for about a year until the arrival of an A&P next door made it necessary for them to specialize; so in 1942 their store became a gourmet delicatessen. About 10 years later, the arrival of another grocery store licensed to sell beer and wine caused the business to be transformed again, this time into a sandwich deli.

"In 1954, we started making sandwiches," Pauline Cohen said. "It was either convert or get out."

The Cohens said the surge of fast-food places has not affected them too much. "They don't hurt you," said Pauline Cohen. "You can't go into those places and get that personal touch."

Jack Cohen estimates he and his wife make about 300 sandwiches a day. He says the favorite changes. "Right now it's the club," he said. "It's popular because it's $1.75."

"They make delicious sandwiches," said Jane Bridgeman, owner of the Arlington Forest Laundramat, located near the deli. "They're going to be missed. I know a lot of people that go over and have lunch there while they're doing their laundry."

The Cohens say they don't have any specific retirement plans. "I don't believe in plans," said Pauline Cohen. "I believe in taking one day at a time."

Asked what advice she would give to a young person opening a deli today, she said: "I'd say make up your mind you're going to marry it and make it a success," she said.